[PATCH 3/5] net: gianfar: fix device leak when querying time stamp info

From: Johan Hovold
Date: Fri Jul 25 2025 - 13:15:09 EST


Make sure to drop the reference to the ptp device taken by
of_find_device_by_node() when querying the time stamping capabilities.

Note that holding a reference to the ptp device does not prevent its
driver data from going away.

Fixes: 7349a74ea75c ("net: ethernet: gianfar_ethtool: get phc index through drvdata")
Cc: stable@xxxxxxxxxxxxxxx # 4.18
Cc: Yangbo Lu <yangbo.lu@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/net/ethernet/freescale/gianfar_ethtool.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/gianfar_ethtool.c b/drivers/net/ethernet/freescale/gianfar_ethtool.c
index 781d92e703cb..c9992ed4e301 100644
--- a/drivers/net/ethernet/freescale/gianfar_ethtool.c
+++ b/drivers/net/ethernet/freescale/gianfar_ethtool.c
@@ -1466,8 +1466,10 @@ static int gfar_get_ts_info(struct net_device *dev,
if (ptp_node) {
ptp_dev = of_find_device_by_node(ptp_node);
of_node_put(ptp_node);
- if (ptp_dev)
+ if (ptp_dev) {
ptp = platform_get_drvdata(ptp_dev);
+ put_device(&ptp_dev->dev);
+ }
}

if (ptp)
--
2.49.1